Intermittent positive pressure breathing device
US4057059A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 1975 |
| Grant date | Nov 8, 1977 |
| Priority date | — |
| Expiry date | Jul 29, 1995 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M16/0051
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A ventilator implemented completely with fluidic devices provides independent control of inhalation time, exhalation time and breathing gas flow rate. The basic fluidic system comprises a low frequency oscillator which in the form of a flip flop is controlled in its two stable states by means of independently controlled time delay relays. The output of the flip flop is amplified by a digital amplifier and operates an on-off valve which is used to direct breathing gas from the source to the patient. Independent control of the flow rate of the breathing gas is by means of a needle valve. With this basic fluidic system, there are seven other features of the apparatus. One is a maximum pressure control which on inhalation is responsive to the patient's breathing air pressure. The second feature is a sensitivity control, which during exhalation is responsive to the patient inspiratory effort. The third feature is a positive end exhalation pressure control. The fourth is an intermittent mandatory ventilation control which permits breathing rates as low as one breath per minute. The fifth feature is a manual control which allows the termination of the exhalation phase and initiation of th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.